Proceedings 2019, 35, 21; doi:10.3390/proceedings2019035021 www.mdpi.com/journal/proceedings Extended Abstract
Serum and Salivary BP180 NC 16a Enzyme-Linked
Immunosorbent Assay in Mucous Membrane
Pemphigoid. Analysis of a Cohort of 25 Patients
†Fedora Della Vella 1,*, Sara Galleggiante 1, Claudia Laudadio 1, Maria Contaldo 2, Dario Di Stasio 2, Marilina Tampoia 1 and Massimo Petruzzi 1
1 Interdisciplinary Department of Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy;
sara.galleggiante@libero.it (S.G.); c.lauda@hotmail.it (C.L.); mtampoia@libero.it (M.T.); massimo.petruzzi@uniba.it (M.P.)
2 Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania “Luigi
Vanvitelli”, 80138 Naples, Italy; maria.contaldo@gmail.com (M.C.); dario.distasio@unicampania.it (D.D.S.)
* Correspondence: dellavellaf@gmail.com; Tel.: +39-3498407957
† Presented at the XV National and III International Congress of the Italian Society of Oral Pathology and Medicine (SIPMO), Bari, Italy, 17–19 October 2019.
Published: 12 December 2019
1. Introduction
Mucous membrane pemphigoid (MMP) is a rare autoimmune blistering disease, affecting one or more mucosae. The oral cavity is generally involved, often in form of desquamative gingivitis (Figure 1).
Immunofluorescence (direct and indirect), histopathology (Figure 2), together with sera autoantibodies dosage by enzyme-linked immunosorbent assay (ELISA) are currently used to diagnose this disease. Saliva is currently employed for diagnostic purposes in multiple fields, providing a wide pool of biomarkers, and representing a not-invasive method suitable for screening and follow-up procedures [1,2].
Figure 1. Desquamative gingivitis: common clinical oral manifestation of mucous membrane
Proceedings 2019, 35, 21 2 of 3
Figure 2. Histopathological picture of MMP (4× magnification).
2. Aim
The aims of the present study were to analyze the efficacy of ELISA in the detection of anti BP180 NC 16a antibodies, comparing salivary and sera specimens, in patients affected by MMP; and to evaluate the correlation between the severity of the clinical manifestations and the anti BP180 titers detected.
3. Materials & Method
Patients referred to Oral Medicine unit of Policlinico di Bari, from January 2011 to December 2016, with a histopathological diagnosis of MMP confirmed by direct immunofluorescence (DIF) test were enrolled. Every patient underwent a serum and a saliva sample collection at the beginning of the diagnostic process. BP180 titers were assessed using commercially available ELISA kit (cut off: 9 U/mL). Clinical Harman’s score was recorded for every patient. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy of ELISA performed on salivary samples were calculated in comparison to sera specimens. The concordance between the two tests was evaluated using the Cohen’s kappa coefficient (k). The correlation between clinical Harman’s scores and ELISA titers was evaluated using t-Student test (significative values with p < 0.05). 4. Results
Twenty-five patients were enrolled, 19 females and 6 males (F:M = 3.16), mean age 63.5 (SD ± 10.9). Patients data are resumed in Table 1. Sensitivity and specificity values were 83.3% and 53.8% respectively, NPV was 77.8% and PPV was 62.5%, accuracy resulted with a value of 68%. The Cohen’s k value was 0.367 (concordance: “fair”). The association between the clinical scores and both the salivary and sera anti-BP180 titers resulted to be statistically significant (p < 0.05).
Table 1. Enrolled patients’ demographic data, anti-BP 180 sera and saliva titers detected using ELISA,
and Harman’s scores. The positive values (>9 U/mL) are bolded.
Patient Sex Age Anti-BP180 Serum Titer Anti-BP180 Saliva Titer Herman Score
1 F 66 6.6 4.5 2 2 F 82 43.2 26 3 3 F 67 13.6 19.7 3 4 M 50 28.8 44.3 1 5 M 59 30 9.1 1 6 F 46 3 11.2 1 7 M 45 0.8 2.9 1 8 F 65 2.3 40.9 2 9 F 82 26.3 11.2 1 10 F 62 3.8 3.3 3 11 F 73 5 42.1 2
Proceedings 2019, 35, 21 3 of 3 12 F 59 8.2 0.5 1 13 F 78 19.4 66.1 3 14 F 56 1.1 2.4 1 15 M 74 6.5 7.2 3 16 F 59 14.3 17.3 1 17 F 48 16.4 2.5 3 18 M 61 12.7 60 1 19 F 74 2 10 3 20 F 77 27.1 13 2 21 F 69 8.3 31.8 1 22 F 65 12.7 46.2 2 23 F 66 0.3 11.7 2 24 F 58 34.8 7.4 2 25 M 47 3.9 7.4 2 5. Discussion
From this study a good sensitivity of ELISA performed on saliva emerged, while specificity resulted lower when compared to sera data. Nowadays, few studies about ELISA effectiveness in patients affected by pemphigoid are available, and even less about muco-membranous forms. The concordance between the two samples used resulted to be fair, suggesting the chance to employ saliva as a not-invasive tool to help the diagnostic process and to track the course of the pathology [1–4]. In fact, this study showed a statistical correlation between clinical conditions and antibodies titers. A greater reliability of ELISA could be achieved extending the range of dosable antigens of the commercial kits, and using crevicular fluid samples instead of whole saliva, providing higher levels of antibodies.
Conflicts of Interest: The authors have no conflict of interests to declare.
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